Inspiron 1440 Beep Codes - 2 beeps

I'm having a similar problem that another person had with an Inspiron 1440.  It belongs to a friend but he's not tech savvy.  It was initially doing the repeated "4 beeps" continuously, so as stated by Dell-Appu, I tried re-seating the DIMMs (The laptop originally came with a single 1 GB SO-DIMM, but at some point it was upgraded and now has a the original, along with a newer 2 GB SO-DIMM as well....for a total 3GB).  He says it was working fine with the 3GB total, for about a year or more.  I tried switching DIMM A,B slots, and also tried each stick individually in slot DIMM A as recommended.  But now the laptop still doesn't boot, and instead of a repeating 4 beeps, it does 2 short beeps (but not continuous), and that's it.  I can't find any info on Dell.com for this 2 beep error.

Please help!  Thank you.